Band-saw mill.



2 SHEETS-SHEET 1.

I ll

[/WENTOR; WQ

Wznv 5555;

B XWWAW V A/zomey/y No. 798,569. PATENTED AUG. 29, 1995. 0. E. CLEVELAND. BAND SAW MILL.

APPLICATION FILED JAN. G, 1904 2 SHEETS-SHBL'T 2.

Arm/me);

VII/filllllll llll I 1:\ IQE mu Amuuwv s. amuuu cm, PHOTWKDGMVHERS. wnsnmavou. n. c.

. CHARLES E. CLEVELAND, OF FOND DU LAC, WISCONSIN.

BAND-SAW MILL.

Specification of Letters Patent.

Patented Aug. 29, 1905.

Application filed January 6, 1904:. Serial lio- 187,953.

To all whom it may concern:

Be it known that I, CHARLEs E. CLEVELAND, a citizen of the United States, residing at Fond du Lac, in the county of Fond du Lac and State of Wisconsin, have invented certain new anduseful Improvements in Band-Saw Mills, of which the following is a specification.

My present invention pertains to improvements in band-saw mills, and more particularly to the saw-straining mechanism, the construction and advantages of which will be hereinafter set forth, reference being had to the annexed drawings, wherein Figure l is a side elevation of the mill embodying my improvements; Fig. 2, a front elevation thereof, the saw being omitted; Fig. 3, a transverse vertical sectional view on the line 3 3 of Fig. 1; Fig. 4, a horizontal sectional view on the line 44 of Fig. 2, and Fig. 5 an enlarged sectional view of the lower end of one of the cylinders and its piston or plunger.

The object of myinvention is to provide an automatic fluid-pressure saw-straining device which can be so regulated as to exert any desired strain upon the saw and maintain the same, notwithstanding fluctuations of pressure in the source of fluid-pressure supn .v-

Broadly stated, the invention comprises an upper band-wheelshaft, aliquid-pressure support therefor having an air-cushion, a source of liquid-pressure connected with said support, and a reducing-valve interposed in the connections intermediate the support and the source of supply.

Referring to the drawings, A denotes a column or support for the upper band-wheel B, said column being, as usual, secured to a base-plate or frame C. The lower bandwheel D and its shaft are supported by suitable hangers E, extending downwardly from said plate or frame C.

F F indicate two cylinders or cylindrically-shaped members attached to or preferably formed integral with a frame or casting Gr, said cylinders being closed at the upper and open at the lower ends. The upwardlyextending ends H H of the cylinders are bored out to receive the downwardly-extending posts I of bearings for the upper bandwheel shaft J. Extending outwardly from each of the cylinders is a T-shaped arm or bracket K, said arms working in similarlyshaped grooves or ways formed in the face of the column, as is best shown in Fig. 4. Se-

cured to the column A in line with the lower ends of the cylinders are fixed pistons or abutments L L, one for each cylinder, the pistons extending upwardly into the cylinders, as shown in Fig. 3. The lower end of each cylinder carries a ring M, which makes a tight joint with the piston, a cup-packingN also being employed to effect a close union between the parts and prevent leakage of the pressure liquid, which passes into the cylinders through pipes O O, tapped into the heads of the pistons. As will be noted upon reference to Fig. 3, the pistons or abutments are of a length less than that of the cylinders, so that an air space or chamber will be formed in the upper end of each cylinder.

Pipes O O are connected to a pipe P, which in turn leads to a reducing-valve Q. A pipe R extends from said valve to the water space or chamber of a steam boiler, and consequently water is forced through the valve Q, which is regulated to close at a predetermined pressure, into the cylinders F and F. The pocketed air in said cylinders, which will of course be compressed, forms a cushion for the shaft-bearings, and inasmuch as the pressure exerted in each cylinder is the same (or approximately so) and both cylinders are connected to or form a part of the frame or casting G the shaft must move up an equal distance at both ends. inders being constant by reason of the employment of the reducing-valve, the strain or pressure exerted upon the saw is likewise constant, notwithstanding fluctuations or variations in the boiler-pressure.

The surface area of the heads of the pistons or abutments L L being known, the reducing-valve may be set to exert any desired pressure per square inch. Consequently the operator can vary or regulate the tension upon the saw to a nicety.

An exhaust or outlet'pipe S is provided for draining the cylinders or reducing the pressure therein when desired.

The pocketed air working in conjunction with the-liquid renders the'deviee highly efficient. The small body of air lends sufficient elasticity to the apparatus to make the same effective, while the liquid-columns render the strain substantially constant, the liquid of course being much less compressible than the air. When steam is employed as the sole medium for elevating the wheel, the compressibility of the entire column and the condensation of the steam are factors which The pressure in the cylrender the mechanism extremely delicate of' band-wheel; a shaft therefor; a pair of cylinders rigidly secured to each other, said cylinders being closed at their upper ends; a shaftbearing carried by each of said cylinders; fixed plungers or abutments, one for each cylinder; and means for admitting liquid under pressure into said cylinders.

2. In a band-saw mill, the combination of a band-wheel; a shaft therefor; a pair of cylinders rigidly'secured to each other, said cylinders being closed at the ends adjacent to the shaft; shaft-bearings carried by the cylinders; fixed pistons or abutments working in the open ends of said cylinders; means for admitting liquid under pressure into said cylinders; and means for maintaining the pressure of said liquid constant,substantially as described.

3. In a band-saw mill, the combination of a support or column; a band-wheel; a shaft therefor; a pair of rigidly-connected cylinders; shaft-bearings carried by said cylinders; guiding connections intermediate the cylinders and the column; fixed pistons or abutments working in the lower end of the cylinders; and means for supplying liquid under pressure to said cylinders.

4:. In a band-saw mill, the combination of a support or column having Ways in its forward face; a band-wheel; a shaft therefor; a pair of cylinders closed at their upper ends; a frame or casting rigidly connecting said cylinders; guides extending from said cylinders and working in the ways in the column; fixed pistons or abutments working in the lower open ends of the cylinders; connections extending from said cylinders to a source of liquid-supply; and a reducing-valve interposed in said connections.

5. In a band-saw mill, the combination of a band-wheel; a shaft therefor; bearings for the shaft; a pair of rigidly-connected cylinders supporting said bearings; fixed pistons or abutments working in the lower open ends of said cylinders; guides for said cylinders; and liquid-pressure mechanism for elevating said cylinders.

6. In a band-saw mill, the combination of a support or column having Ways formedin its forward face; a band-saw wheel; a shaft therefor; a pair of cylinders closed at their upper ends; shaft-bearings carried by said cylinders; a frame or casting rigidly connecting said cylinders; guides extending from said cylinders and working in the ways formed in the column; fixed pistons or abutments working in the lower open ends of said cylinders, said pistons or abutments being of a length less than that of the cylinders; means for securing a tight joint between said cylinders and pistons; a source of liquid-pressure connected to the cylinders; and a reducingvalve for controlling the pressure.

7. In a band-saw mill, the combination of a band-saw wheel; a shaft therefor; a pair of cylinders closed at one .end; bearings for the shaft carried by the cylinders; fixed abutments working in said'cylinders, said abutments being of a length less than that of the cylinders, whereby an air pocket or chamber is formed in the upper closed end of each cylinder; and means for admitting liquid under pressure into said cylinders.

In testimony whereof I have signed my name to this specification in the presence of two subscribing witnesses.

CHARLES E. CLEVELAND.

Witnesses:

WILLIAM MCDERMOTT, ALICE I. YAPP. 

